With the availability of newer and more reliable fabrication technologies, nanopore sensors (e.g., single molecule sensor) and nanoscale filters have rapidly become rising stars in many fields including biomedical diagnostics, and water quality monitoring and improvement. In order to detect and analyze minute amounts of analytes, in some cases, even a single biomolecule (DNA, RNA, protein and so on), nanopore sensors generally apply a voltage across a thin solid-state material (e.g., silicon-based membranes, and graphene) and/or a biological material (e.g., a lipid bilayer), and aims to detect when the ionic currents through nanometer-scale apertures are transiently changed by the translocation of, e.g., electrophoretically or otherwise driven biomolecules through the tiny apertures. For example, well built nanopore sensors can detect that the passage of RNA or single-stranded DNA molecules through a membrane-embedded alpha-hemolysin channel (1.5 nm in diameter) causes a ˜90% blockage of the current when measured in a 1 M potassium chloride (KCl) solution.
Nanopore sensors find a wide range of applications in medicine, biological research, analytical chemistry, agriculture, food safety, environmental protection, fuel cell chemistry, and so on. For example, nanopore technology is promising the availability of much cheaper and faster DNA sequencing technology and new therapeutics for diabetic patients.
However, all nanopore sensing applications are challenged by limited control over surface chemistry as described in further detail below. Accordingly, there is a strong need for an easier, consumer-scale fabrication method to overcome the costly overhead and poor reliability issues that plague conventional silane chemistry.